问题:
I ______ the blackboard carefully, but I can ______ nothing.
[ ]
A. look,seer
B. look at, see
C. see, look
D. see, look at
I ______ the blackboard carefully, but I can ______ nothing.
B. look at, see
C. see, look
D. see, look at
[ ]
A. look,seer B. look at, see
C. see, look
D. see, look at
参考答案: